Render mutates locals hash?

Rails
1

If you pass a locals hash into render() … why would Rails mutate that
hash, adding things to it? This seems awfully odd to me.

Could have something to do with calling partials inside partials, which
I am doing. Does the locals hash ‘inherit’ to the ‘inner’ partial?
That’s kind of odd.

I just traced a weird bug in my app down to this – I was storing locals
in an actual hash data structure, instead of using an anonymous hash,
and wasn’t counting on rails changing in between calls!

By "freeze"ing the thing that I didn’t expect to get modified, I could
get this stack trace pointing to what’s doing the modifying, but I
haven’t looked at it yet.

/usr/lib/ruby/gems/1.8/gems/actionpack-2.1.2/lib/action_view/partial_template.rb:48:in

[]=' /usr/lib/ruby/gems/1.8/gems/actionpack-2.1.2/lib/action_view/partial_template.rb:48:inadd_object_to_local_assigns!’
/usr/lib/ruby/gems/1.8/gems/actionpack-2.1.2/lib/action_view/partial_template.rb:9:in
`initialize’

2

On Jun 9, 10:35 pm, Jonathan R. <rails-mailing-l…@andreas-
s.net> wrote:

If you pass a locals hash into render() … why would Rails mutate that
hash, adding things to it? This seems awfully odd to me.

Rails has a hash of those local variables that should be created
inside a partial (for example if you are rendering a collection then
the current object in that collection is assigned to the appropriate
local variable name). If you supply a hash it uses that (perhaps it
should dup the hash you provide). This shouldn’t have anything todo
with rendering partials from partials

Fred